More fabulous fabulation on the theme of time-travel and its paradoxical implications for the unfortunate Trafalgar Hurlock and the rest of the Evolution Limitation Volunteers. In E.L.V. I, Trafalgar's team had discovered John, the practical joker who invented the mice who have destroyed the post-sleep world's data banks of history. Now they need to put things right for the future -- but that proves easier said than done. Bouncing around between the Stone Age, Florence in 1506 and a Roman amphitheatre, every correction that the team makes seems to lead to another historical paradox.